Punishment?

There are several students being "punished" right now. They are squatting in the office, waiting to talk to their teacher that is punishing them. However, they still have their cell phones and are just text messaging. Is that really a punishment? We have kids frequently who are in a kind of "in school suspension" where their desks are in the hall outside of the teacher's office. However, the kids have their phones and mp3 players, and are usually just sleeping all day. How is this a type of punishment? I don't get it. Doesn't seem to teach anything to me. Doesn't seem to make them behave any better. Doesn't stop anything.